Assuming that's a serious question, I think it refers to the original meaning of commute = reduce. The extension of the word to daily travel to work is, AIUI, an American usage in that what we'd call a season ticket, is a commuted fare. People buying season tickets are commuters and eventually, all daily travellers became commuters, whether season ticket holders or not.

I'm not sure that's correct. I think the origin of commute is to do with change from one state to another rather than reduction. For instance, alchemists would talk of commuting lead into gold. From com (with) and mute = change. cf transmute, mutate, permutation. So commuting in the context of travel is regularly changing your place (between work and home).

However, I asssume mjr was making a pun rather than a serious enquiry.